In a variety of subsea well related applications, hydraulically operated intervention equipment is deployed at the seabed or at other subsea locations. The hydraulically operated equipment requires a relatively large sized multi-hose hydraulic control umbilical with each hydraulic hose in the umbilical designated to control a unique equipment function. For example, two hoses in a hydraulic umbilical can be designated for opening and closing a valve in a subsea test tree. The technique requires the use of a bespoke umbilical and associated spooling/handling equipment able to deploy the umbilical into a drilling riser and down to the subsea equipment. The umbilical is routed down through the drilling riser and coupled to hydraulic porting in a tubing hanger running tool.
In one variation, an electro-hydraulic multiplex control system can be employed to facilitate control of the subsea equipment with fewer hydraulic hoses running from the surface. This type of control system can be operated to redirect hydraulic fluid along a variety of different hydraulic flow paths to control various mechanical functions. However, the electro-hydraulic multiplex control system still requires a hydraulic umbilical that is routed down through the drilling riser to enable operation of the subsea intervention equipment. The appropriate spooling/handling equipment also must be mounted on the surface rig to handle the umbilical, thus requiring substantial, valuable rig space.